I'm in the city/hill and I can't see any words to go with the phone call.
This is a bug on our end, we've submitted a fix and expect it to go live a couple days after release. For the time being you should be able to progress by closing out of the call. Once you get the new version you can go back to the calls and fill in the gaps. Sorry about this!
What's with the text in the 3rd tutorial that says "Unhandled Exception: System.NullReferenceException:" etc.?
This isn't a bug! We meant to do that. That's all we can really say about that though!
If you have any other issues let us know via electronic mail.
It's probably secure.